Disney executives have "watered down" scenes from Rogue One: A Star Wars Story, including one where Darth Vader lays waste to an entire Rebel ground squad, according to a user who says he has had a hand in the spin-off.

Redditor KeepR1Dark made the claim after starting a new thread on which he has purportedly leaked details about the film's plot, characters and casting. He says he decided to answer questions on Rogue One to make Disney back down from the changes it has reportedly ordered.

The user also confirms one of the biggest rumours, saying that Darth Vader does appear in the hotly anticipated film.

"In a night scene Vader absolutely lays waste to a Rebel ground Squad," KeepR1Dark writes. "Unfortunately this is one of the scenes we have to water down. We made it like something from the old slasher/horror films. Rebel soldiers who joked about a boogie man with magical powers and then minutes later are absolutely wasted."

In addition, there will be an appearance from "a huge A lister who has one line but I don't want to spoil it because we're keeping that and it's such an awesome 'what the hell' moment".

Some have speculated this could be Obi Wan Kenobi.

Later in the thread, another Redditor asks whether Disney's claim that the reshoots were simply intended to "take the film from good to great" was merely a smokescreen?

"Yes," KeepR1Dark replies. "They want a movie that kids can watch too because that will net the most money. [Director] Gareth [Edwards] is livid."

Reddit moderators have attempted to verify KeepR1Dark's identity but have so far failed to get the assurances they demand. Consequently, they have posted a note warning caution about the claims. However, Reddit has yet to mark the thread as "fake", leaving open the possibility that KeepR1Dark's assertions may be authentic.